Ablation catheters, which can be used to necrotize or ablate bodily tissue in vessels or hollow organs at an exact point using electrothermal means and with all of the advantages of minimally invasive surgery, have been known and used in clinical applications for a long time. They are used, inter alia, to remove selected regions of excitable cardiac tissue within the scope of treatment of cardiac arrhythmias. To ensure successful use thereof, it is of considerable—and often decisive—significance that the operating surgeon be able to assess the quality of the contact between an electrode mounted on the distal catheter end or another ablation element and the bodily tissue.
Ablation catheters are also known, which are provided with outlet openings (irrigation openings) by way of irrigation channels in the distal region, which are intended for delivering fluids to the treatment site in order to cool surrounding tissue at this point or, optionally, to wash away ablated tissue components. The irrigation channels are connected, by way of a central lumen in the catheter body at the proximal end of the catheter, to a pump which is used to supply fluid from an irrigation fluid reservoir. Such an ablation catheter, which is referred to in the following as an irrigation catheter device, is described in European Patent No. EP 2 343 022, for example.
The present invention is directed toward overcoming one or more of the above-identified problems. A problem addressed by the present invention is that of providing an improved irrigation catheter device which can be used simultaneously as means for determining the presence and the quality of a contact with surrounding bodily tissue.